ffmpeg/libavutil/bswap.h

100 lines
2.4 KiB
C

/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file libavutil/bswap.h
* byte swapping routines
*/
#ifndef AVUTIL_BSWAP_H
#define AVUTIL_BSWAP_H
#include <stdint.h>
#include "config.h"
#include "common.h"
#if ARCH_ARM
# include "arm/bswap.h"
#elif ARCH_BFIN
# include "bfin/bswap.h"
#elif ARCH_SH4
# include "sh4/bswap.h"
#elif ARCH_X86
# include "x86/bswap.h"
#endif
#ifndef bswap_16
static av_always_inline av_const uint16_t bswap_16(uint16_t x)
{
x= (x>>8) | (x<<8);
return x;
}
#endif
#ifndef bswap_32
static av_always_inline av_const uint32_t bswap_32(uint32_t x)
{
x= ((x<<8)&0xFF00FF00) | ((x>>8)&0x00FF00FF);
x= (x>>16) | (x<<16);
return x;
}
#endif
#ifndef bswap_64
static inline uint64_t av_const bswap_64(uint64_t x)
{
#if 0
x= ((x<< 8)&0xFF00FF00FF00FF00ULL) | ((x>> 8)&0x00FF00FF00FF00FFULL);
x= ((x<<16)&0xFFFF0000FFFF0000ULL) | ((x>>16)&0x0000FFFF0000FFFFULL);
return (x>>32) | (x<<32);
#else
union {
uint64_t ll;
uint32_t l[2];
} w, r;
w.ll = x;
r.l[0] = bswap_32 (w.l[1]);
r.l[1] = bswap_32 (w.l[0]);
return r.ll;
#endif
}
#endif
// be2me ... big-endian to machine-endian
// le2me ... little-endian to machine-endian
#ifdef WORDS_BIGENDIAN
#define be2me_16(x) (x)
#define be2me_32(x) (x)
#define be2me_64(x) (x)
#define le2me_16(x) bswap_16(x)
#define le2me_32(x) bswap_32(x)
#define le2me_64(x) bswap_64(x)
#else
#define be2me_16(x) bswap_16(x)
#define be2me_32(x) bswap_32(x)
#define be2me_64(x) bswap_64(x)
#define le2me_16(x) (x)
#define le2me_32(x) (x)
#define le2me_64(x) (x)
#endif
#endif /* AVUTIL_BSWAP_H */